Abstract
Present study was aimed to investigate the role of selenium in amelioration of cadmium stress in Chlamydomonas reinhardtii. Cadmium treatment growth declined by reducing the pigment synthesis and increasing the oxidative damage to membranes. Selenium supplementation caused a significant decline in hydrogen peroxide production and hence the rate of lipid peroxidation which was well correlated with the increase in the activities of antioxidant enzymes including superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase. Proline increased due to supplementation of selenium and optimised the synthesis of nitric oxide for better counteracting the cadmium stress. Supplementation of selenium protected membrane structures in C. reinhardtii from the cadmium stress by maintaining the higher contents of polyunsaturated fatty acids.